I'm always for having more characters. Mostly because I love making them. I have over 50 OCs in reserve. All I do is tweak the nature of their power to match their dimension. Like Aya could easily work in Naruto or Bleach. Just change mutant to chakra or Reiatsu. But I have two I really wanna use. Either my cyborg T.E.A.C.S.U.N. 5 or Skittles. Although Skittles might qualify as OP because while her powers are low.... she has seven personalities, each with a different attribute to the power. Like Violette is very serious and has piercing beams, while Rouge is lustful and has fire beams. Bleue has debilitating beams and is sad, but Jaune has electric beams and is happy! She's really fun, but I don't know if she could work here.

On a side note, I'm glad there are more danger rooms. Aya is REALLY going to need to vent some steam.